Modified dot-ELISA for diagnosis of human trichinellosis.

This study aimed to modify Dot-Enzyme-linked immunosorbent assay (dot-ELISA) for the diagnosis of human trichinellosis and to compare its performance with indirect ELISA and Western-blot assay (EITB). A total of 175 human serum samples were enrolled in the study. Indirect ELISA was used for the primary diagnosis. EITB versus fractionated 1st larval stage excretory-secretory antigens (TL-1 ESA) revealed three specific protein fractions at MW of 45, 50, and 55 kDa (kDa). Dot-ELISA was performed in two ways. In the first one, sera were dotted on the separated three specific protein fractions, while in the second one the three fractions were eluted, concentrated at one pooled antigen that used in classic dot-ELISA. Both types of dot-ELISA proved absolute (100%) sensitivity and specificity in comparison with the gold standard EITB reaction. While sensitivity of ELISA was 100% and its specificity was 79.5%. The fraction at 45 kDa was the most sensitive one. The use of the pooled antigen improved the test results. The described dot-ELISA is an easy applicable diagnostic tool gathering the benefits of both ELISA and EITB.

Molecular seasonality of Giardia lamblia in a cohort of Egyptian children: a circannual pattern.

Giardia lamblia (G. lamblia) is the most worldwide prevailing intestinal parasite, notorious for its broad range of seasonal and age-related prevalence. The potentially lethal nature of giardiasis makes it essential that the seasonality, the groups at risk, and other potential risk factors are identified. The present molecular epidemiological study was designed to determine the genetic diversity of G. lamblia infection, taking into account seasonal peaks, age distribution, and associated symptoms in a cohort of Egyptian diarrheic patients. Stool samples were collected from 1187 diarrheic patients attending outpatient clinics of Cairo University hospitals, of all age groups over a 12-month period. The patients were examined microscopically for fecal G. lamblia cysts, and/or trophozoites, and for copro-DNA detection using nested polymerase chain reaction (nPCR) assays targeting beta giardin gene. PCR-positive samples were characterized molecularly by nPCR restriction fragment length polymorphism (RFLP) to determine Giardia assemblages. The findings revealed circannual prevalence of Giardia, with a seasonal pattern peaking in mid-summer and late winter, with the summer peak preceded by a peak in temperature. Infection was prevailing in 224 (18.9 %) cases, mainly assemblage B (81.2 %) followed by assemblage A (18.8 %). There were statistically significant associations between the detection of Giardia and flatulence, persistent diarrhea, vomiting, and abdominal pain, while gender and intermittent diarrhea showed no association. The pre-school age group was the most vulnerable. This is the first study of molecular characterization of Giardia to determine its circannual prevalence in Egypt, a finding which carries promising potential for the diagnosis, treatment, and elimination of the disease.